Oder River

The Oder River is 531 miles long. It begins in the Czech Republic and flows through western Poland. As it moves through Poland, it becomes part of the Oder-Neisse line, forming the border between Poland and Germany. Eventually, it flows into the Szczecin Lagoon, which is shared by Poland and Germany. Here it splits into three branches that empty into the Bay of Pomerania of the Baltic Sea. After World War II, the Oder became the far eastern border of Germany.